Warranty woes

On 10 October 2021,I logged a call issue @ hisense customer care and a proof of purchase was required.I then explained that the tv bought was in 2019 and as a present.Several days later I then went to the store to get the POP but then realised that my father's card had changed so we had to go back to request the card number that was then used.From 20 October 2021,game stores was given the card number and transaction date.They then had to go through archives to get the POP which I then provided.Now Hisense's service desk is saying what was provided can't be used? How cos what game provided is the same as what appeared on the till slip? Is this a way of hisense not to honor their warranty promise? I found out that the tv model is no longer stocked or made by Hisense.This says don't purchase hisense products if you need that peace of mind